The Battle of Fontenoy, May 11, 1745, is a major engagement of the War of the Austrian Succession, fought between the forces of the Pragmatic Allies – comprising mainly Dutch, British, and Hanoverian troops under the command of the Duke of Cumberland – and a French army under Maurice de Saxe, commander of King Louis XV's forces in the Low Countries.

The battle is notable for several reasons.

It is one of the most important in the war, and for the French a famous victory and the masterpiece of Marshal Saxe; the French Monarch Louis XV and his son the Dauphin are present on the field.

Napoleon I later declares that the victory at Fontenoy prolonged the Ancien Régime monarchy in France by 30 years.

Saxe goes on the offensive in April 1745 with a large French army, looking to build on the previous year's gains.

His initial aim is to take control of the upper Scheldt basin and thereby gain access to the heart of the Austrian Netherlands.

To these ends, he first pounces on the fortress of Tournai, protecting the siege with his main force about 5 miles (~9 km) south-east of the town.

In order to relieve Tournai, the Allies first decide to attack Saxe's position – a naturally strong feature, hinged on the village of Fontenoy and further strengthened by defensive works.

After failing to make progress on the flanks – the Dutch on the left, Brigadier Ingolsby's brigade on the right – Cumberland decides to smash his way through the center without securing the flanks of his main attack.

Despite devastating flanking fire the Allied column, made up of British and Hanoverian infantry, bursts through the French lines to the point of victory.

Only when Saxe concentrates all available infantry, cavalry, and artillery is the column forced to yield.

The Allies retreat in good order, conducting a fighting withdrawal.

The battle has shown, however, the strength of a defensive force relying on firepower and a strong reserve.Casualties ware high on both sides, but the French have gained the field, and Tournai falls shortly after the battle.

This success is followed by a rapid advance against the less organized and outnumbered Allied army: Ghent, Oudenarde, Bruges, Dendermonde soon fall to French forces.

The British army's withdrawal to England to deal with the Jacobite Rebellion facilitates the French capture of the strategically important ports of Ostend and Nieuwpoort, threatening Britain's links to the Low Countries.

By the year's end, Saxe has completed the conquest of much of the Austrian Netherlands, and with his successes he becomes a national hero in his adopted country.

The battle has established the French superiority in force and high command.